ul li p7312019 D1 OSI vs TCP IPp p11p pI`qcx =4 @rrial`gkp p@rrial`gkI`qcx 54 Rxcck~`gkp pI`qcx 34 cagkp pI`qcx 4 ^x`krgx~ ^x`krgx~p pI`qcxp li ul